It is now well established that putting an infant to sleep on his or her back is the single most important step in reducing the risk of sudden infant death syndrome (SIDS).
Recent research also suggests that a baby's risk for SIDS can be greatly reduced by using a pacifier. Medical research also shows that babies who can satiate their natural sucking reflex sleep better. Experts recommend giving babies a pacifier every time they are placed to sleep. The exact reason that pacifiers reduce the risk of SIDS is not known. One suggestion is that the presence of a pacifier in the mouth may discourage babies from turning over onto their tummy because turning or moving may dislodge the pacifier. Another suggestion is that pacifier use and/or the sucking reflex helps keep the tongue positioned forward, keeping the airways open. Yet another suggestion is that pacifiers stimulate upper airway muscles and saliva production, so using pacifiers may keep babies from falling into a deep sleep, which is protective against SIDS.
One of the factors that has led to a revival in the ancient practice of swaddling is the practice of putting babies to sleep on their backs as this helps to reduce the incidence of SIDS. However, babies tend to sleep better on their tummies than on their backs. Swaddling has been found to assist infants sleep more comfortably on their backs and to assist in easing colic, which also improves sleep. Swaddling is the practice of wrapping infants tightly in a blanket or cloth so that movement of the limbs is restricted.
Medical research has shown that swaddling and sleeping supine (on the back) promotes more efficient sleep, with fewer spontaneous awakenings compared with sleeping supine but unswaddled. Swaddling seems to inhibit each step from sighs through startles to full arousal in the arousal pathway. This results in swaddled babies sleeping longer and being more likely to return to sleep on their own: Swaddling: a systematic review, Bregje E. van Sleuwen, et al, Pediatrics vol 120, number 4, October 2007.
To achieve the benefits of swaddling, infants need to be wrapped sufficiently tight to restrain the limbs and inhibit the movements associated with a full startle reflex, which can wake babies from sleep. The startle reflex is seen in infants from birth to around 6 months of age (some sources indicate it can occur in infants as old as eight months). The startle reflex is a natural reflex that babies are born with, and can be triggered by loud noise or sudden movement. In response to the trigger, the baby throws back his/her head, extends out the arms and legs, cries, then pulls the arms and legs back in. A baby's own cry can trigger the reflex. It can also be triggered during sleep, causing the baby to wake.
Care needs to be taken not to swaddle too tightly because this can compress the chest and make breathing difficult. There is also an increased risk of overheating especially when the head is covered or when there is infection. Improper swaddling can also lead to a risk of hip dysplasia (including hip dislocation) especially when swaddling with the hips and legs in extension and adduction (i.e. drawn toward the midline or sagittal plane of the body).
Other risks associated with swaddling babies includes an increased risk of SIDS when a swaddled infant is placed prone (on his or her front) or able to turn to prone position. The SIDS risk seems to be increased by swaddling with the head covered. There is also a slightly increased risk of acute respiratory infections, which seems to be related to the tightness of swaddling. These are discussed in the systematic review of swaddling referred to above.
Therefore, to swaddle properly and effectively, and to achieve the desired result, the blanket must be snug enough to immobilise the infant's arms, and to a certain degree its legs, but loose enough that it is still comfortable and not increase the risk of hip dysplasia or suppressed respiration.
Many parents and carers experience difficulty with swaddling due to unfamiliarity with swaddling techniques. If not swaddled correctly, the infant often wriggles free of the swaddle thus becoming exposed to a risk of suffocation or SIDS-related issues due to loose bedding and unrestricted positioning of the infant. However, swaddling alone cannot eliminate these risks. This is especially true for infants that are more than around six weeks old, when they are stronger and more active than newborns. Even when swaddled tightly with all limbs securely enclosed, infants can potentially roll, becoming entrapped in the swaddling blanket or trapped face down while still wrapped in the blanket.
To overcome the difficulty faced by parents and carers in learning proper swaddling techniques and to address the problems of improper swaddling, various swaddling suits have been developed. Swaddling suits such as the infant safety suit of WO 2007/098558 (the Snuggo), the Ergococcoon and the Woombi address the problems of wrapping too loosely or too tightly since the degree of wrapping is predetermined by the suit.
As mentioned above, recent evidence shows that sucking on a pacifier is protective against SIDS. In addition, supplemental non-nutritive sucking (that is, sucking in addition to that required for feeding) is known to help to soothe an infant. Researchers have discovered that there is a clear reflex connection between the hand and mouth of a human fetus as early as 12-14 weeks after conception, and that thumb sucking in utero is common. After birth, many infants continue to soothe themselves by sucking on their thumbs or fingers. A newborn's ability to get the hands up to his or her mouth and suck is seen as a positive ability of the infant to organize him or herself in a self-soothing way. This helps establish an infant's ability to independently cope with stress and frustration.
Thus it would be an advantage to have a swaddle suit that overcomes the problems of improper swaddling and also provides an opportunity for non-nutritive sucking. This would improve the calming effect of the swaddling suit, since research that indicates that multiple simultaneous measures such as swaddling and sucking (along with rocking, white noise and other interventions) have an additive calming effect on crying infants: Karp H, Swaddling and excessive crying, Journal of Pediatrics, July 2007, e2. None of the aforementioned swaddling suits facilitates non-nutritive sucking.
None of WO 2007/098558 (the Snuggo), the Ergococcoon or the Woombi provide access to the hands while the infant is swaddled. Movement of the infant's arms in all three of these swaddling suits is restricted to 180 degrees below the shoulder line so the hands are restrained near the body but below the shoulder line, out of reach of the mouth.
U.S. Pat. No. 7,587,769 is a swaddling article including a blanket formed with opposed arm-receiving sleeves that attempts to facilitate non-nutritive sucking by securing a pacifier to the blanket, thus overcoming the problem of pacifiers falling out of an infant's mouth. The blanket incorporates a pacifier retaining structure to retain a pacifier relative to the blanket so that the pacifier is unable to fall away from the blanket. This keeps the pacifier positioned near the mouth when the blanket is wrapped around an infant so it is available for the infant to suck on at will. The pacifier retaining structure includes a flap of fabric secured to the upper edge of the swaddling blanket. The flap is drawn across the region of the baby's mouth.
A disadvantage of the swaddling article of U.S. Pat. No.7,587,769 is that it relies on a pacifier to be secured to the blanket. Another disadvantage is that it essentially extends the blanket across the face (around the mouth region), which can be uncomfortable and covering the face during sleep increases the risk of SIDs. Yet another disadvantage is that the swaddle article is in the form of a modified blanket and so lacks the convenience and advantages of a swaddling suit for example, the risk remains that the swaddle may loosen through movement thus becoming less effective and also posing a suffocation risk.
While research indicates that there are benefits associated with non-nutritive sucking (e.g. pacifier use), it also indicates that pacifier use may be associated with problems including:
interference with breast feeding,
dependence on the pacifier (so the baby cannot sleep without one),
an increased risk of middle ear infections, and
dental problems associated with prolonged use.
Hence, despite the established benefits of pacifier use, many parents choose not to use pacifiers. Further, some infants simply do not take to pacifiers. In any event, so as to minimise interference with breastfeeding, the recommendation is to wait until nursing is going well (usually one month) before offering a pacifier. Thus pacifier use is not suitable for all infants and it would be an advantage to provide a means for non-nutritive sucking that does not rely on pacifier use.
Reflexes are set motor responses to specific sensory stimuli. Newborns have a hand-to-mouth reflex that is a natural instinct to get their hands to their mouths. Research indicates that this ability to access the hands for sucking is important for self-soothing. The hand-to-mouth reflex (along with the startle reflex) is one of a number of primitive reflexes present from birth or earlier. Primitive reflexes are thought to have provided evolutionary advantages to humans.
The somatosensory system is a complex system of receptors and processing centres that produce the senses including touch, motion perception (proprioception) and balance, and spatial perception of body parts (kinesthesia). The tactile or skin senses (that rely on skin sensors for touch and pressure) appear first during fetal development. The vestibular system, which is responsible for movement and balance perception, and the tactile (touch) sensors are highly developed in newborns.
The hand-to-mouth reflex goes with two reflexes that are considered essential to appropriate feeding responses in newborns: the rooting (or search) reflex and the sucking reflex. Both of these reflexes are triggered by a touch (including pressure) stimulus.
The rooting reflex occurs when the infant's cheek or corner of the mouth is touched or stroked. The infant's mouth opens to follow and “root” (search) in the direction of stroking or touch. Rooting helps the baby to become ready to suck. The suckling reflex is triggered by touching the mucous membranes on the inside of the mouth with any object. Both reflexes facilitate nursing.
In the hand-to-mouth reflex, when an infant's cheek is stroked, his or her mouth roots and the arm flexes. After hand and mouth find each other, the infant may suck energetically on the hands.
There is a need for a swaddling suit that does not suffer the disadvantages of a swaddling using a blanket and that effectively swaddles infants by sufficiently restraining movement of the limbs to suppress the startle reflex, yet still affords sufficient movement so that infants can get their hand(s) toward their mouth, so providing the opportunity for non-nutritive sucking without reliance on a pacifier.
U.S. Pat. No. 4,611,353 describes a swaddling garment in which an infant's arms are gently bound in a bent-elbow, hands-up position to inhibit the ability to fling open the arms without restricting arm movement. Binding of the arms in this manner is described as useful for holding a premature infant.
The BabySense Cuddlewrap is a blanket shaped to wrap an infant's arms tightly near to the body and face, again as a means for suppressing jerks of the arms and legs. However, neither the manufacturer of the BabySense Cuddlewrap nor the inventor of garment of U.S. Pat. No. 4,611,353 refer to the benefit of providing access to the hands for non-nutritive sucking while swaddled and neither swaddle addresses this need adequately.
While the swaddle of U.S. Pat. No. 4,611,353 is referred to as a garment, the part of the garment that is responsible for binding the arms in the manner described is two flaps of sufficient length to wrap around the infant and overlap each other, secured in place either by strips of hook and loop fasteners or simply by relying on the length of the flaps. Thus binding of the arms is achieved by a length of fabric in a manner analogous to a blanket. Loosening of the binding is possible with movement/wriggling of the baby—particularly in the embodiment that relies on the length of the flaps to secure the wrapping around the infant or where the hook and loop fastening is not sufficient to restrain loosening of the flaps through wriggling movement of the infant.
Therefore, the risks associated with use of swaddling blankets or cloths remain with both the BabySense Cuddlewrap and the swaddle of U.S. Pat. No. 4,611,353, including:
1. wrapping too tightly so as to suppress respiration;
2. overwrapping the infant in several layers of fabric so as to increase the risk of overheating (particularly as the preferred embodiment of U.S. Pat. No. 4,611,353 also includes a hood);
3. loosening of the swaddle around the upper body will result in excess fabric around the upper body, posing a suffocation risk to the infant;
4. the arms are only restrained so long as the swaddle remains tightly secured around the infant and loosening allows increasing movement of the arms;
5. the swaddle does not facilitate or maintain access to the hands, although access can initially be provided depending on how the hands are positioned when the infant is first swaddled.
Thus both U.S. Pat. No. 4,611,353 and the BabySense Cuddlewrap share many of the disadvantages of swaddling using a blanket, and do not act to secure the hands in position near the face to provide the opportunity for non-nutritive sucking without reliance on a pacifier.
It is an object of the present invention to provide a new or alternative swaddling suit that swaddles infants by restraining movement of the limbs and which overcomes the disadvantages of other swaddling suits by allowing movement of the hand towards the mouth and maintaining the hand in a position relative to the infant's face thereby facilitating non-nutritive sucking.